The goods are classified according to the Standard International Trade Classification(SITC), drawn up by the United Nations to facilitate the international comparability of international trade statistics. The SITC consists of 10 sections (0-9) which are divided into a total 67 divisions (00-97). The divisions can be further broken down into groups with 3-digit codes. StatLine accommodates data at section and division level. Information on groups can be requested from the department of international trade statistics of Statistics Netherlands, in writing or by telephone.

Time series break 2007/2008. Dutch imports and exports are being calculated slightly differently in 2008 than in earlier years. The causes are a different boundary between re-exports and transit trade and taking into account some small enterprises that erroneously were not included in the trade statistics. It is expected that these two changes will not have an effect on the total imports. The exports will be around 3 billion euro, less than 1 percent of the total yearly exports, smaller than when these changes would not have been implemented. On a more detailed level, relatively larger differences can appear. More information about this time series break can be found (in Dutch) on the International Trade theme page.

Imports - All goods introduced into the free economic trade of the Netherlands for use or consumption. i.e. goods for which import duties and national taxes have been paid. Imports including goods imported temporarily into the Netherlands which, by commission of a non-resident, undergo treatment (active finishing trade); and goods from non-EU countries which enter the economic trade in the Netherlands via bonded warehouses. The statistical value is the value of the goods at the moment they cross the border. For imports from EU countries this value is inclusive of freight and insurance charges up to the Dutch border. For imports from non-EU countries this value is inclusive of freight and insurance charges up to the border of the European Union.

Exports - All goods intended for use or consumption outside the Netherlands. These are goods manufactured in or originally imported into the Netherlands. Exports including goods exported temporarily from the Netherlands which, by commission of a Dutch resident living abroad, undergo treatment (passive finishing trade). The statistical value is the value of the goods at the moment they cross the border. For exports this value is the value of the goods inclusive of freight and insurance charges up to the Dutch border.

Balance of trade - The value of exports minus the value of imports.

Total countries (groups) - The (groups) of countries include the Netherlands' most important trading partners. Statistical information is presented on 66 individual countrieswhich cover approximately 95 % of Dutch imports and exports. The remaining countries are subsumed in rest groups according to their geographical location.

The realisation of the internal European market on 1 January 1993 had drastic effects on international trade statistics. Until then, companies were obliged to report all imports and exports in writing to the customs authorities. As borders between EU countries were abolished for the purposes of international trade, it was no longer possible to compile figures on goods trade between EU countries with the aid of customs forms. In order to be able to continue to observe this trade a new system was set up to collect the necessary information. This new system, called INTRASTAT, is based on the direct supply of data on imports and exports by companies to Statistics Netherlands. Information on trade with countries outside the EU, the so-called third countries, are still obtained by customs.

The figures have been corrected for non-response and for companies below the survey threshold of 400,000 Euro (was 225,000 Euro) (companies which import or export goods worth 400,000 Euro (was 225,000 Euro) or more to or from EU countries are obliged to report the statistics of their transactions to Statistics Netherlands).

The accuracy and reliability of statistics depend on a number of factors: the adequacy of the available basic information, the statistical techniques used, the validation of the basic material or of intermediate or final results, and the available information on revisions. Accuracy refers to the inherent non-knowable difference between an estimated and the 'real' value of the phenomenon being measured. Although no definite statements can be made about the accuracy of published statistics on international trade, this does not mean that no supplementary information can be collected. An authoritative IMF framework 1) includes revisions under reliability. In some quality assessments (by Eurostat among others) the element revisions is included under the aspect stability. The underlying concept is the same: revisions serve to eliminate the difference between the first and subsequent estimates of the value measured. To measure reliability, therefore, successive estimates are compared. In other words: reliability is connected to revisions. Statistics Netherlands is currently developing a number of accuracy and reliability indicators for international trade statistics, to be published in StatLine in due course. One possibility in this respect is to do this within the annual Quality Report which is to be compiled annually by all EU countries from 2005 onwards. These reports will include the following subjects: relevance, accuracy (survey thresholds, non-response), revisions, confidentiality and consequent information loss, timeliness, accessibility, comparability,coherence and completeness.

The international trade figures can be adjusted based on the availability of new source material. As such, the figures remain preliminary for a substantial period of time. The figures are first available eight weeks after the reference period. The preliminary figures are adjusted well over three months after the quarter of reference. In the third quarter of the year t + 1 the monthly figures become definitive and are the final annual figure available on StatLine.

In some cases import and/or export figures may not be published, or only be published partly, because of confidentiality regulations. Such cases occur when the figures can be traced back to individual companies, and publication would be detrimental to the interest of these companies. In international trade statistics, the passive confidentiality regulations apply, i.e. the companies concerned must formally request Statistics Netherlands not to publish their figures.